FOX LAKE, Ill. – Police in northern Illinois say one of the suspects in a police officer’s killing is in custody, CNN reports. A manhunt is underway for two other suspects. The officer was shot and killed Tuesday around 7:50 a.m.

The officer has been identified as Charles Joseph Gliniewicz, a 32-year-veteran of the Fox Lake Police Department, the Chicago Tribune reports. Gliniewicz leaves behind four sons.

Lake County Undersheriff Raymond Rose says the officer was pursuing people described as suspicious when he was shot and killed in Fox Lake, 55 miles north of Chicago. Rose tells the Chicago Tribune that other responding officers found him in a marshy area and that he was stripped of his gun and other equipment.

Rose says police are searching for two other suspects. Law enforcement officers are conducting a massive manhunt with helicopters and dogs.